No ranking of tributaries is attempted, as the concept is too contentious; for example, hydrologically the middle and upper Volga could be considered a tributary of the Kama, in which case it would be the fifth or sixth longest river in Europe. read more
The Volga River is the longest river in Europe. The river is 2,290 miles long and is located entirely in Russia. It begins in the Valdai Hills near Rzhev and flows south to the Caspian Sea. read more